Fence panel sections are typically made up of pickets and rails. In aluminum fencing, the pickets normally are aluminum extrusions, as are the rails. Typically, the rails are screwed to the pickets to form a fence panel that is mounted between larger upright posts. Such fence panels can be assembled at a factory and then shipped as already assembled panels. However, this results in a bulkier shipment, limiting the number of fence panels that can be shipped in a container of a given size.
The fence panels can be shipped as components only and then assembled by the end user or installer. Shipping the components unassembled increases shipping density (lowering shipping costs). However, pre-assembled panels are easier for the end user or installer to work with, so there is some market resistance to purchasing fence panels from unassembled components.